[Federal Register Volume 63, Number 48 (Thursday, March 12, 1998)]
[Rules and Regulations]
[Pages 11985-11987]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-6329]



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Rules and Regulations
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Federal Register / Vol. 63, No. 48 / Thursday, March 12, 1998 / Rules 
and Regulations

[[Page 11985]]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-NM-39-AD; Amendment 39-10384; AD 98-06-07]
RIN 2120-AA64


Airworthiness Directives; Fokker Model F28 Mark 0100 Series 
Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This amendment supersedes an existing airworthiness directive 
(AD), applicable to certain Fokker Model F28 Mark 0100 series 
airplanes, that currently requires a revision to the Airplane Flight 
Manual (AFM) to include procedures to prohibit use of reverse engine 
thrust power settings between idle and emergency maximum. This 
amendment revises the existing AFM revision requirement, and adds a new 
revision to the AFM to prohibit stabilized engine operation in a 
certain engine speed range on the ground. This amendment is prompted by 
issuance of mandatory continuing airworthiness information by a foreign 
civil airworthiness authority. The actions specified in this AD are 
intended to prevent stabilized engine operation in a certain engine 
speed range on the ground, which could result in uncontained engine fan 
blade failure due to high cycle fatigue cracking.

DATES: Effective March 27, 1998.
    Comments for inclusion in the Rules Docket must be received on or 
before April 13, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 98-NM-39-AD, 1601 Lind Avenue, SW., Renton, 
Washington 98055-4056.

FOR FURTHER INFORMATION CONTACT: Norman B. Martenson, Manager, 
International Branch, ANM-116, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
227-2110; fax (425) 227-1149.

SUPPLEMENTARY INFORMATION: On October 15, 1997, the FAA issued AD 97-
19-16, amendment 39-10169 (62 FR 54579, October 21, 1997), applicable 
to certain Fokker Model F28 Mark 0100 series airplanes, to require a 
revision to the FAA-approved Airplane Flight Manual (AFM) to include 
procedures to prohibit use of reverse engine thrust power settings 
between idle and emergency maximum. That AD also requires submission of 
a report to the airplane manufacturer if the limits are exceeded. That 
action was prompted by a report that, during preparation for takeoff, 
an engine fan blade failure occurred, followed by an engine fire. The 
actions required by that AD are intended to prevent uncontained engine 
fan blade failure due to high cycle fatigue cracking, which could 
result in loss of thrust from the affected engine and secondary damage 
to aircraft and/or fire.

Actions Since Issuance of Previous Rule

    Since the issuance of that AD, the Rijksluchtvaartdienst (RLD), 
which is the airworthiness authority for the Netherlands, notified the 
FAA that new engine operating limitations are necessary to prevent high 
cycle fatigue cracking of the engine fan blades. The RLD advises that 
stabilized engine operation in the speed range between 60 and 75 
percent low pressure rotational speed (N1) during ground operations in 
forward or reverse thrust may cause high fan blade stresses and 
resultant high cycle fatigue cracking. This condition, if not 
corrected, could result in uncontained engine fan blade failure.
    The RLD classified these limitations as mandatory and issued Dutch 
airworthiness directive 1997-110/2 (A), dated January 30, 1998, in 
order to assure the continued airworthiness of these airplanes in the 
Netherlands. The Dutch airworthiness directive adds certain statements 
to clarify the operating limitation that prohibits use of reverse 
engine thrust power settings between idle and emergency maximum. In 
addition, the Dutch airworthiness directive also specifies that 
inspections of Rolls-Royce Tay 650 series engines are to be 
accomplished if the operating limits discussed previously have been 
exceeded.

FAA's Conclusions

    This airplane model is manufactured in the Netherlands and is type 
certificated for operation in the United States under the provisions of 
section 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and 
the applicable bilateral airworthiness agreement. Pursuant to this 
bilateral airworthiness agreement, the RLD has kept the FAA informed of 
the situation described above. The FAA has examined the findings of the 
RLD, reviewed all available information, and determined that AD action 
is necessary for products of this type design that are certificated for 
operation in the United States.

Explanation of Requirements of Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop on other airplanes of the same type design registered 
in the United States, this AD supersedes AD 97-19-16 to continue to 
require revising the AFM to prohibit use of reverse thrust power 
settings between idle and emergency maximum. This AD also deletes the 
reporting requirement contained in AD 97-19-16, since engine 
inspections have been defined for cases where limits have been 
exceeded.
    This AD adds a requirement to revise the AFM to prohibit stabilized 
engine operation in the speed range between 60 and 75 percent low 
pressure rotational speed (N1) during ground operations in forward or 
reverse thrust.

Differences Between This AD and the Dutch Airworthiness Directive

    This AD differs from the parallel Dutch airworthiness directive in 
that it does not mandate the accomplishment of certain engine 
inspections for airplanes on which the new engine limits are exceeded. 
(These inspections also are specified in British airworthiness 
directive 001-12-97.) The FAA may consider further rulemaking to 
address the associated engine inspection requirements.
    In addition, this AD differs from the parallel Dutch airworthiness 
directive in that this AD specifically limits the

[[Page 11986]]

maximum reverse thrust lever positions to the idle detent position for 
normal operation. This change is necessary to ensure that the 
limitations are clearly understood by the flightcrew.

Interim Action

    This is considered to be interim action until final action is 
identified, at which time the FAA may consider further rulemaking.

Determination of Rule's Effective Date

    Since a situation exists that requires the immediate adoption of 
this regulation, it is found that notice and opportunity for prior 
public comment hereon are impracticable, and that good cause exists for 
making this amendment effective in less than 30 days.

Comments Invited

    Although this action is in the form of a final rule that involves 
requirements affecting flight safety and, thus, was not preceded by 
notice and an opportunity for public comment, comments are invited on 
this rule. Interested persons are invited to comment on this rule by 
submitting such written data, views, or arguments as they may desire. 
Communications shall identify the Rules Docket number and be submitted 
in triplicate to the address specified under the caption ADDRESSES. All 
communications received on or before the closing date for comments will 
be considered, and this rule may be amended in light of the comments 
received. Factual information that supports the commenter's ideas and 
suggestions is extremely helpful in evaluating the effectiveness of the 
AD action and determining whether additional rulemaking action would be 
needed.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the rule that might 
suggest a need to modify the rule. All comments submitted will be 
available, both before and after the closing date for comments, in the 
Rules Docket for examination by interested persons. A report that 
summarizes each FAA-public contact concerned with the substance of this 
AD will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this rule must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 98-NM-39-AD.'' The postcard will be date stamped and 
returned to the commenter.

Regulatory Impact

    The regulations adopted herein will not have substantial direct 
effects on the States, on the relationship between the national 
government and the States, or on the distribution of power and 
responsibilities among the various levels of government. Therefore, in 
accordance with Executive Order 12612, it is determined that this final 
rule does not have sufficient federalism implications to warrant the 
preparation of a Federalism Assessment.
    The FAA has determined that this regulation is an emergency 
regulation that must be issued immediately to correct an unsafe 
condition in aircraft, and that it is not a ``significant regulatory 
action'' under Executive Order 12866. It has been determined further 
that this action involves an emergency regulation under DOT Regulatory 
Policies and Procedures (44 FR 11034, February 26, 1979). If it is 
determined that this emergency regulation otherwise would be 
significant under DOT Regulatory Policies and Procedures, a final 
regulatory evaluation will be prepared and placed in the Rules Docket. 
A copy of it, if filed, may be obtained from the Rules Docket at the 
location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

Adoption of the Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration amends part 39 of 
the Federal Aviation Regulations (14 CFR part 39) as follows:

PART 39--AIRWORTHINESS DIRECTIVES

    1. The authority citation for part 39 continues to read as follows:

    Authority: 49 U.S.C. 106(g), 40113, 44701.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by removing amendment 39-10169 (62 FR 
54579, October 21, 1997), and by adding a new airworthiness directive 
(AD), amendment 39-10384, to read as follows:

98-06-07 Fokker: Amendment 39-10384. Docket 98-NM-39-AD. Supersedes 
AD 97-19-16, amendment 39-10169.

    Applicability: Model F28 Mark 0100 series airplanes equipped 
with Rolls-Royce (RR) Tay 650-15 engines, certificated in any 
category.

    Note 1: This AD applies to each airplane identified in the 
preceding applicability provision, regardless of whether it has been 
modified, altered, or repaired in the area subject to the 
requirements of this AD. For airplanes that have been modified, 
altered, or repaired so that the performance of the requirements of 
this AD is affected, the owner/operator must request approval for an 
alternative method of compliance in accordance with paragraph (c) of 
this AD. The request should include an assessment of the effect of 
the modification, alteration, or repair on the unsafe condition 
addressed by this AD; and, if the unsafe condition has not been 
eliminated, the request should include specific proposed actions to 
address it.

    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent stabilized engine operation in a certain engine speed 
range on the ground, which could result in uncontained engine fan 
blade failure due to high cycle fatigue cracking, accomplish the 
following:
    (a) Within 72 hours after October 27, 1997 (the effective date 
of AD 97-19-16, amendment 39-10169), revise the Limitations Section, 
Subsection 2.06.01 ``Thrust Reverser,'' of the FAA-approved Airplane 
Flight Manual (AFM) to add the following. This may be accomplished 
by inserting a copy of this AD in the AFM.

``THRUST REVERSER

    Thrust reversers are intended for ground use only. Intentional 
use of reverse thrust in flight is prohibited. After reverse thrust 
has been initiated, a full stop landing must be made.

Maximum Reverse Thrust Lever Positions

    Normal Operation:
    --The idle detent position shall not be exceeded in normal 
operation.
    Emergency Operation:
    --In case of emergency, the emergency maximum reverse thrust may 
be used.
    --Stabilized operation with the reverse lever in an intermediate 
position between idle reverse and emergency maximum reverse is 
prohibited.
    --If directional control problems occur, select forward idle.
    Exceeding the idle reverse thrust limitations must be 
reported.''
    (b) Within 72 hours after the effective date of this AD, remove 
the revision to the Limitations Section of the FAA-approved Airplane 
Flight Manual (AFM) required by AD 97-19-16, amendment 39-10169, and 
revise the Limitations Section of the FAA-approved AFM to add the 
following. This may be accomplished by inserting a copy of this AD 
in the AFM.

``LIMITATIONS

POWERPLANT and APU LIMITATIONS

OPERATING LIMITS

     To avoid high fan blade stresses, stabilized operation 
in the speed range between 60% and 75% Low Pressure Rotational Speed 
(N1) is not permitted during Ground Operations in Forward or Reverse 
Thrust, except that passing through this range while increasing or 
decreasing thrust is permitted.

[[Page 11987]]

THRUST REVERSER

    Thrust reversers are intended for ground use only. Intentional 
use of reverse thrust in flight is prohibited. After reverse thrust 
has been initiated, a full stop landing must be made.

Maximum Reverse Thrust Lever Positions

    Normal Operation:
    --The idle detent position shall not be exceeded in normal 
operation.
    --Momentarily exceeding the idle detent position, while 
selecting idle reverse, is acceptable.
    Emergency Operation:
    --In case of emergency, the emergency maximum reverse thrust may 
be used.
    --If directional control problems occur, reduce to idle reverse 
or select forward idle.
    --Stabilized operation with the reverse lever in an intermediate 
position between idle reverse and emergency maximum reverse is 
prohibited, except (where approved) during Power-Back operations.''

    Note 2: Fokker Services Manual Change Notification--Operational 
Documentation (MCNO) No. F100-006, dated November 27, 1997, contains 
information that pertains to this subject. Rolls-Royce PLC Engine 
Operating Instruction Manual Reference F-TAY-3RR, revised by 
transmittal letter No. 13 dated October 15, 1997, also pertains to 
this subject.
    (c) An alternative method of compliance or adjustment of the 
compliance time that provides an acceptable level of safety may be 
used if approved by the Manager, International Branch, ANM-116, FAA, 
Transport Airplane Directorate. Operators shall submit their 
requests through an appropriate FAA Principal Operations Inspector, 
who may add comments and then send it to the Manager, International 
Branch, ANM-116.

    Note 3: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the International Branch, ANM-116.

    (d) Special flight permits may be issued in accordance with 
sections 21.197 and 21.199 of the Federal Aviation Regulations (14 
CFR 21.197 and 21.199) to operate the airplane to a location where 
the requirements of this AD can be accomplished.

    Note 4: The subject of this AD is addressed in Dutch 
airworthiness directive 1997-110/2 (A), dated January 30, 1998.

    (e) This amendment becomes effective on March 27, 1998.

    Issued in Renton, Washington, on March 5, 1998.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 98-6329 Filed 3-11-98; 8:45 am]
BILLING CODE 4910-13-U